Toronto/Taipei, May 25 (Reuters): Canadian health officials are monitoring 33 people for the SARS virus with another 500 in quarantine just 10 days after the World Health Organisation said the virus was no longer spreading in the country.

While hospital emergency rooms in Canada’s biggest city went back on high alert, hard-hit Taiwan spurned an offer by rival China to help the self-governing island fight the Severe Acute Respiratory Syndrome and said its outbreak was under control.

Hong Kong, with the second largest number of SARS cases after mainland China, reported four deaths and one more case, a day after it reported no new infections for the first day since SARS hit the city in March.

Health officials in Toronto said the public should not panic, but the news has prompted the US Centers for Disease Control to tell travellers to take care if they visit the city. For weeks it seemed Canada’s battle with SARS was over. No new cases had been recorded since April 19, a month after the outbreak started in Canada. The possible SARS cases, up from 25 on Friday, raised concerns that the WHO may again slap a travel advisory on Canada’s financial hub.

“Economically, this is far worse than the fallout from the terrorist attacks,” Rod Seiling, president of the Greater Toronto Hotel Association, said.

The disease has killed 24 people in Toronto, the only place outside Asia where there have been SARS deaths. Officials are also investigating two more deaths to determine if they are SARS related.

Taiwan, which has the world’s third-highest number of SARS infections, reported 22 new cases and another 12 deaths, but a health official told reporters the spread had stabilised. “The SARS epidemic has stabilised, but it does not mean we can relax vigilance. We are not saying everything is OK,” said Lee Ming-liang, head of the Cabinet’s SARS committee.